1. Field of the Invention
This invention relates to an apparatus for supplying radial tire blanks to a tire building machine for the purpose of transforming green cases into toroidal shapes and joining tread bands onto the toroidal green cases.
2. Description of the Prior Art
A radial tire includes ply cords of a carcass, which reinforce the tire and are arranged in a plane including a tire rotating axis (namely a radial plane) or a plane slightly oblique to the plane. In view of the so-called hoop effect caused by a belt surrounding the carcass, cords of the belt are generally arranged at very slight angles to a plane perpendicular to the above radial plane. In manufacturing the radial tire, in general, the following processes have been effected. Cord plies mainly for a carcass are turned up so as to enclose a pair of beads and joined to a green rubber member about a building drum to form a so-called generally cylindrical green case. On the other hand, ends of cord layers are joined to form endless cord layers to be adapted to a crown portion of the green case when it is transformed into a toroidal shape. An extruded unvulcanized rubber is then applied onto the endless cord layers to form a so-called tread band. The green case and the tread band are combined on a forming drum to form a so-called green tire which is then subjected to forming and vulcanization in a vulcanizing apparatus.
In these processes, there are two forming steps, that is, for the green case and for the green tire. The latter forming step for the green tire is often referred to as "second forming step". Heretofore, there has been great loss of time in transferring and handling the green case for the second forming step. Accordingly, it has been expected for long years to propose a mechanism for supplying tire forming blanks to a tire building machine which eliminates the loss of time to improve the productivity of tires.